While it may not be THE reason to come to Boston, it might make sense to grab this free driving tour of Boston and see a few locations around town that are meaningful to JFK. You can download the file to a Garmin or TomTom, or just follow some printed directions to get from historical place to historical place. The tour was assembled by the Boston Globe, and put up by Geovative, where you can find a lot of other GPS tours for download.

More at Geovative and the Boston Globe